Treatment of wet clarified sewage sludge used in agriculture

摘要

Treatment of wet clarified sewage sludge (I) comprises: (a) dewatering by mixing with a predetermined amt. of absorptive cellulose material (II) to 25-60% dry matter; (b) waiting until the absorptive capacity of (II) is exhausted; and (c) adding 100-150 kg CaO/tonne mixt. of (I) + (II). (I) is pref. activated sludge (IA) and is mixed with paper fibres (IIA) in an amt. of 20-30 kg/100 kg (IA), esp. after adding Ca(OH)2; or (I) is pressed sludge and is mixed with upto 20 kg (IIA)/kg. (IIA) comprises pulverised paper, free from plastics. The mixt. of (I) and (IIA) is mixed with CaO in a vessel consisting (partly) of Fe.